Two of the BBC's five digital-only stations saw big quarterly drops in their audiences despite the continued growth of digital platforms.

BBC 6Music, home to Adam Buxton and Joe Cornish and controversial morning presenter George Lamb, saw its audience fall by 12.6% to 595,000 in the second quarter of this year, according to official Rajar listening figures published today.

Archive comedy and drama station BBC7's audience fell by 15.2% on the previous three months, to 834,000.

The better news for the stations was that they were both up year on year, 6Music by 8% and BBC7 by 2.7%.

Digital platforms continue to grow in popularity, accounting for 21.1% of all radio listening in the second quarter of the year, up from 20.1% in the previous three months and 17.9% in the same period in 2008.

Digital audio broadcasting (DAB) remains by far the most popular platform, with a 13.1% share of listening, up from 12.7% in the previous three months and 11% in the same period last year.

Of the other digital platforms, digital TV has a 3.6% share, the internet 2.2%, with a further 2.1% unspecified by the listeners taking part in the Rajar survey.

Despite its quarterly decline, BBC7 remains the BBC's most popular digital-only station. Black music station 1Xtra was the biggest winner year on year, up 29.1% to 634,000.

5 Live Sports Extra and the Asian Network were both up on the previous quarter but down year on year, the sports network slipping 9.6% to 676,000, while the Asian Network fell 11% across the year, to 421,000.

The BBC World Service had 1.44 million listeners in the UK, up from 1.31 million last year but down from the record 1.47 million domestic audience in the first three months of this year.

The number of adults who claim to have a DAB set at home grew to 33%, up from 32.1% in the previous quarter and 28.7% in the same period last year.

The number of people who claim to have ever listened to the radio via a mobile phone was 13.9%, up from 12.2% last year. The figure among 15- to 24-year-olds rises to 32.8%.

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